/***************************************************************************/
/*                                                                         */
/*  ftdriver.h                                                             */
/*                                                                         */
/*    FreeType font driver interface (specification).                      */
/*                                                                         */
/*  Copyright 1996-2001, 2002, 2003, 2006, 2008 by                         */
/*  David Turner, Robert Wilhelm, and Werner Lemberg.                      */
/*                                                                         */
/*  This file is part of the FreeType project, and may only be used,       */
/*  modified, and distributed under the terms of the FreeType project      */
/*  license, LICENSE.TXT.  By continuing to use, modify, or distribute     */
/*  this file you indicate that you have read the license and              */
/*  understand and accept it fully.                                        */
/*                                                                         */
/***************************************************************************/


#ifndef __FTDRIVER_H__
#define __FTDRIVER_H__


#include <ft2build.h>
#include FT_MODULE_H


FT_BEGIN_HEADER


typedef FT_Error
(*FT_Face_InitFunc)(FT_Stream stream,
                    FT_Face face,
                    FT_Int typeface_index,
                    FT_Int num_params,
                    FT_Parameter* parameters);

typedef void
(*FT_Face_DoneFunc)(FT_Face face);


typedef FT_Error
(*FT_Size_InitFunc)(FT_Size size);

typedef void
(*FT_Size_DoneFunc)(FT_Size size);


typedef FT_Error
(*FT_Slot_InitFunc)(FT_GlyphSlot slot);

typedef void
(*FT_Slot_DoneFunc)(FT_GlyphSlot slot);


typedef FT_Error
(*FT_Size_RequestFunc)(FT_Size size,
                       FT_Size_Request req);

typedef FT_Error
(*FT_Size_SelectFunc)(FT_Size size,
                      FT_ULong size_index);

#ifdef FT_CONFIG_OPTION_OLD_INTERNALS

typedef FT_Error
(*FT_Size_ResetPointsFunc)(FT_Size size,
                           FT_F26Dot6 char_width,
                           FT_F26Dot6 char_height,
                           FT_UInt horz_resolution,
                           FT_UInt vert_resolution);

typedef FT_Error
(*FT_Size_ResetPixelsFunc)(FT_Size size,
                           FT_UInt pixel_width,
                           FT_UInt pixel_height);

#endif /* FT_CONFIG_OPTION_OLD_INTERNALS */

typedef FT_Error
(*FT_Slot_LoadFunc)(FT_GlyphSlot slot,
                    FT_Size size,
                    FT_UInt glyph_index,
                    FT_Int32 load_flags);


typedef FT_UInt
(*FT_CharMap_CharIndexFunc)(FT_CharMap charmap,
                            FT_Long charcode);

typedef FT_Long
(*FT_CharMap_CharNextFunc)(FT_CharMap charmap,
                           FT_Long charcode);


typedef FT_Error
(*FT_Face_GetKerningFunc)(FT_Face face,
                          FT_UInt left_glyph,
                          FT_UInt right_glyph,
                          FT_Vector* kerning);


typedef FT_Error
(*FT_Face_AttachFunc)(FT_Face face,
                      FT_Stream stream);


typedef FT_Error
(*FT_Face_GetAdvancesFunc)(FT_Face face,
                           FT_UInt first,
                           FT_UInt count,
                           FT_Int32 flags,
                           FT_Fixed* advances);


/*************************************************************************/
/*                                                                       */
/* <Struct>                                                              */
/*    FT_Driver_ClassRec                                                 */
/*                                                                       */
/* <Description>                                                         */
/*    The font driver class.  This structure mostly contains pointers to */
/*    driver methods.                                                    */
/*                                                                       */
/* <Fields>                                                              */
/*    root             :: The parent module.                             */
/*                                                                       */
/*    face_object_size :: The size of a face object in bytes.            */
/*                                                                       */
/*    size_object_size :: The size of a size object in bytes.            */
/*                                                                       */
/*    slot_object_size :: The size of a glyph object in bytes.           */
/*                                                                       */
/*    init_face        :: The format-specific face constructor.          */
/*                                                                       */
/*    done_face        :: The format-specific face destructor.           */
/*                                                                       */
/*    init_size        :: The format-specific size constructor.          */
/*                                                                       */
/*    done_size        :: The format-specific size destructor.           */
/*                                                                       */
/*    init_slot        :: The format-specific slot constructor.          */
/*                                                                       */
/*    done_slot        :: The format-specific slot destructor.           */
/*                                                                       */
/*                                                                       */
/*    load_glyph       :: A function handle to load a glyph to a slot.   */
/*                        This field is mandatory!                       */
/*                                                                       */
/*    get_kerning      :: A function handle to return the unscaled       */
/*                        kerning for a given pair of glyphs.  Can be    */
/*                        set to 0 if the format doesn't support         */
/*                        kerning.                                       */
/*                                                                       */
/*    attach_file      :: This function handle is used to read           */
/*                        additional data for a face from another        */
/*                        file/stream.  For example, this can be used to */
/*                        add data from AFM or PFM files on a Type 1     */
/*                        face, or a CIDMap on a CID-keyed face.         */
/*                                                                       */
/*    get_advances     :: A function handle used to return advance       */
/*                        widths of `count' glyphs (in font units),      */
/*                        starting at `first'.  The `vertical' flag must */
/*                        be set to get vertical advance heights.  The   */
/*                        `advances' buffer is caller-allocated.         */
/*                        Currently not implemented.  The idea of this   */
/*                        function is to be able to perform              */
/*                        device-independent text layout without loading */
/*                        a single glyph image.                          */
/*                                                                       */
/*    request_size     :: A handle to a function used to request the new */
/*                        character size.  Can be set to 0 if the        */
/*                        scaling done in the base layer suffices.       */
/*                                                                       */
/*    select_size      :: A handle to a function used to select a new    */
/*                        fixed size.  It is used only if                */
/*                        @FT_FACE_FLAG_FIXED_SIZES is set.  Can be set  */
/*                        to 0 if the scaling done in the base layer     */
/*                        suffices.                                      */
/* <Note>                                                                */
/*    Most function pointers, with the exception of `load_glyph', can be */
/*    set to 0 to indicate a default behaviour.                          */
/*                                                                       */
typedef struct  FT_Driver_ClassRec_
{
    FT_Module_Class root;

    FT_Long face_object_size;
    FT_Long size_object_size;
    FT_Long slot_object_size;

    FT_Face_InitFunc init_face;
    FT_Face_DoneFunc done_face;

    FT_Size_InitFunc init_size;
    FT_Size_DoneFunc done_size;

    FT_Slot_InitFunc init_slot;
    FT_Slot_DoneFunc done_slot;

    #ifdef FT_CONFIG_OPTION_OLD_INTERNALS

    FT_Size_ResetPointsFunc set_char_sizes;
    FT_Size_ResetPixelsFunc set_pixel_sizes;

    #endif /* FT_CONFIG_OPTION_OLD_INTERNALS */

    FT_Slot_LoadFunc load_glyph;

    FT_Face_GetKerningFunc get_kerning;
    FT_Face_AttachFunc attach_file;
    FT_Face_GetAdvancesFunc get_advances;

    /* since version 2.2 */
    FT_Size_RequestFunc request_size;
    FT_Size_SelectFunc select_size;

} FT_Driver_ClassRec, * FT_Driver_Class;


/*
 *  The following functions are used as stubs for `set_char_sizes' and
 *  `set_pixel_sizes'; the code uses `request_size' and `select_size'
 *  functions instead.
 *
 *  Implementation is in `src/base/ftobjs.c'.
 */
#ifdef FT_CONFIG_OPTION_OLD_INTERNALS

FT_BASE(FT_Error)
ft_stub_set_char_sizes(FT_Size size,
                       FT_F26Dot6 width,
                       FT_F26Dot6 height,
                       FT_UInt horz_res,
                       FT_UInt vert_res);

FT_BASE(FT_Error)
ft_stub_set_pixel_sizes(FT_Size size,
                        FT_UInt width,
                        FT_UInt height);

#endif /* FT_CONFIG_OPTION_OLD_INTERNALS */

/*************************************************************************/
/*                                                                       */
/* <Macro>                                                               */
/*    FT_DECLARE_DRIVER                                                  */
/*                                                                       */
/* <Description>                                                         */
/*    Used to create a forward declaration of a                          */
/*    FT_Driver_ClassRec stract instance.                                */
/*                                                                       */
/* <Macro>                                                               */
/*    FT_DEFINE_DRIVER                                                   */
/*                                                                       */
/* <Description>                                                         */
/*    Used to initialize an instance of FT_Driver_ClassRec struct.       */
/*                                                                       */
/*    When FT_CONFIG_OPTION_PIC is defined a Create funtion will need    */
/*    to called with a pointer where the allocated stracture is returned.*/
/*    And when it is no longer needed a Destroy function needs           */
/*    to be called to release that allocation.                           */
/*    fcinit.c (ft_create_default_module_classes) already contains       */
/*    a mechanism to call these functions for the default modules        */
/*    described in ftmodule.h                                            */
/*                                                                       */
/*    Notice that the created Create and Destroy functions call          */
/*    pic_init and pic_free function to allow you to manually allocate   */
/*    and initialize any additional global data, like module specific    */
/*    interface, and put them in the global pic container defined in     */
/*    ftpic.h. if you don't need them just implement the functions as    */
/*    empty to resolve the link error.                                   */
/*                                                                       */
/*    When FT_CONFIG_OPTION_PIC is not defined the struct will be        */
/*    allocated in the global scope (or the scope where the macro        */
/*    is used).                                                          */
/*                                                                       */
#ifndef FT_CONFIG_OPTION_PIC

    #ifdef FT_CONFIG_OPTION_OLD_INTERNALS
        #define FT_DEFINE_DRIVERS_OLD_INTERNALS(a_, b_) \
    a_, b_,
    #else
        #define FT_DEFINE_DRIVERS_OLD_INTERNALS(a_, b_)
    #endif

    #define FT_DECLARE_DRIVER(class_) \
    FT_CALLBACK_TABLE \
    const FT_Driver_ClassRec class_;

    #define FT_DEFINE_DRIVER(class_, \
                             flags_, size_, name_, version_, requires_, \
                             interface_, init_, done_, get_interface_, \
                             face_object_size_, size_object_size_, \
                             slot_object_size_, init_face_, done_face_, \
                             init_size_, done_size_, init_slot_, done_slot_, \
                             old_set_char_sizes_, old_set_pixel_sizes_, \
                             load_glyph_, get_kerning_, attach_file_, \
                             get_advances_, request_size_, select_size_) \
    FT_CALLBACK_TABLE_DEF \
    const FT_Driver_ClassRec class_ = \
    { \
        FT_DEFINE_ROOT_MODULE(flags_, size_, name_, version_, requires_, interface_, \
                              init_, done_, get_interface_) \
 \
        face_object_size_, \
        size_object_size_, \
        slot_object_size_, \
 \
        init_face_, \
        done_face_, \
 \
        init_size_, \
        done_size_, \
 \
        init_slot_, \
        done_slot_, \
 \
        FT_DEFINE_DRIVERS_OLD_INTERNALS(old_set_char_sizes_, old_set_pixel_sizes_) \
 \
        load_glyph_, \
 \
        get_kerning_, \
        attach_file_, \
        get_advances_, \
 \
        request_size_, \
        select_size_ \
    };

#else /* FT_CONFIG_OPTION_PIC */

    #ifdef FT_CONFIG_OPTION_OLD_INTERNALS
        #define FT_DEFINE_DRIVERS_OLD_INTERNALS(a_, b_) \
    clazz->set_char_sizes = a_; \
    clazz->set_pixel_sizes = b_;
    #else
        #define FT_DEFINE_DRIVERS_OLD_INTERNALS(a_, b_)
    #endif

    #define FT_DECLARE_DRIVER(class_)    FT_DECLARE_MODULE(class_)

    #define FT_DEFINE_DRIVER(class_, \
                             flags_, size_, name_, version_, requires_, \
                             interface_, init_, done_, get_interface_, \
                             face_object_size_, size_object_size_, \
                             slot_object_size_, init_face_, done_face_, \
                             init_size_, done_size_, init_slot_, done_slot_, \
                             old_set_char_sizes_, old_set_pixel_sizes_, \
                             load_glyph_, get_kerning_, attach_file_, \
                             get_advances_, request_size_, select_size_) \
    void class_##_pic_free(FT_Library library); \
    FT_Error class_##_pic_init(FT_Library library); \
 \
    void \
    FT_Destroy_Class_##class_(FT_Library library, \
                              FT_Module_Class * clazz) \
    { \
        FT_Memory memory = library->memory; \
        FT_Driver_Class dclazz = (FT_Driver_Class)clazz; \
        class_##_pic_free(library); \
        if (dclazz) \
            FT_FREE(dclazz); \
    } \
 \
    FT_Error \
    FT_Create_Class_##class_(FT_Library library, \
                             FT_Module_Class * *output_class) \
    { \
        FT_Driver_Class clazz; \
        FT_Error error; \
        FT_Memory memory = library->memory; \
 \
        if (FT_ALLOC(clazz, sizeof(*clazz))) \
            return error; \
 \
        error = class_##_pic_init(library); \
        if (error) \
        { \
            FT_FREE(clazz); \
            return error; \
        } \
 \
        FT_DEFINE_ROOT_MODULE(flags_, size_, name_, version_, requires_, interface_, \
                              init_, done_, get_interface_) \
 \
        clazz->face_object_size = face_object_size_; \
        clazz->size_object_size = size_object_size_; \
        clazz->slot_object_size = slot_object_size_; \
 \
        clazz->init_face = init_face_; \
        clazz->done_face = done_face_; \
 \
        clazz->init_size = init_size_; \
        clazz->done_size = done_size_; \
 \
        clazz->init_slot = init_slot_; \
        clazz->done_slot = done_slot_; \
 \
        FT_DEFINE_DRIVERS_OLD_INTERNALS(old_set_char_sizes_, old_set_pixel_sizes_) \
 \
        clazz->load_glyph = load_glyph_; \
 \
        clazz->get_kerning = get_kerning_; \
        clazz->attach_file = attach_file_; \
        clazz->get_advances = get_advances_; \
 \
        clazz->request_size = request_size_; \
        clazz->select_size = select_size_; \
 \
        *output_class = (FT_Module_Class*)clazz; \
        return FT_Err_Ok; \
    }


#endif /* FT_CONFIG_OPTION_PIC */

FT_END_HEADER

#endif /* __FTDRIVER_H__ */


/* END */